But Alaska executives are still showing concern about a flood of new seats on their home turf.

Delta Air Lines is rapidly adding domestic and international flights at Seattle's airport as it builds up a new Pacific gateway there. Much of that new service overlaps with Alaska Airlines.

Andrew Harrison, Alaska's senior vice president for planning, told Wall Street analysts that his carrier is holding its own.

"Our second quarter results give us confidence we are on the right track," Harrison said.

He said his airline is planning more aggressive advertising, improvements to food and wine offerings, and to strengthen its frequent flier program.

"We are making some tactical schedule adjustments to increase our flying in some of these markets to defend our franchise," he said. "This may have short-term impact. But we believe the water will find its level eventually. We are confident these are the right actions for us."

Wall Street seems less confident. Alaska Air Group Inc. stock plummeted 9.4 percent over the course of Thursday's trading, to close at $45.03 per share.

During a briefing call for Wall Street analysts Wednesday, Delta's president Ed Bastian called out the good performance at its new Seattle gateway. He said his airline's new flights are "doing well" revenue-wise.